It happened out of the blue... any idea what could have caused this? I already emailed vanguard as instructed with no response. Curious as to how this could happen without any physical damage done.

Thank you in advance.

Not sure why you got no response but that's something that has to change , we have seen some screen issues lately and are working on finding the fault, if yours is a manufacture problem, it will get sorted out. I can't tell you a reason why it would happen like that, sorry.